John snow was a famous doctoc in London-so expert,indeed,that he attended Queen Victoria as personal. But he became inspired when he thought about helping ordinary people exposed to cholera.This was the deadlly disease of its day.Neither its cause nor its cure was understood.So many thousands of terrified people died everytime there was an outbreak.John Snow wanted to face the challenge and solve this problem.He knew that cholera would never be controlled until its cause was found.

John Snow(约翰·斯诺）是伦敦的一位非常出名的医生，并且是维多利亚女王的私人医生。当他考虑帮助那些受霍乱之苦的普通人的时候，他被震撼了。在那个年代，霍乱是致命的。但是无论是霍乱的起因还是治愈方法都不为人知。每次在霍乱爆发的时候，都有数以千计的人们带着恐惧死去。约翰·斯诺想面对这个挑战并解决这个问题，他知道只有找到霍乱的病因才能控制它。